Deterioration and impact - resistant wooden surfaces and bowling pins



INQ

ETAL 3,220,731 ACT-RESISTANCE WOODEN LING PINS M IMP Nov. 30, 19

- GE AND DETERIQ CES AN ow FIG. 2

' NmRs No lNo ND J MOSHY FELIX SEPH RAYMO RICHAR BY Md [W ATTORNEY.

United States Patent 3,220,731 DETERIORATION AND IMPACT-RESISTANT WOODENSURFACES AND BOWLING PINS Felix .l. Germino, Peekskill, and Joseph R.Infantino,

Chappaqua, N.Y., Raymond J. Moshy, Westport, (Iona,

and Richard A. Smith, Cornwall on the Hudson, N.Y.,

assignors to American Machine & Foundry Company,

a corporation of New Jersey Filed Apr. 5, 1961, Ser. No. 100,885 14Claims. (Cl. 27382) This invention relates to wooden surfaces and woodenarticles imparted with resistance against deterioration and damage fromimpact. In a more specific application this invention relates to bowlingpins.

It is generally recognized that wood surfaces have a tendency tosplinter, dent, chip, check, pit and have grain separation weaknesses inuse. The defects become particularly apparent when the wooden surface orarticle is subjected to impact or rough usage as for example withbowling pins or bats. Dehydration of the internal composition of thewood also results in the deterioration of the wooden article. This alsoconsiderably shortens the useful life of wood articles.

The invention and its advantages is applicable generally to woodensurfaces. It is attractive especially in connection with wooden articlessubject to severe usage, as for example: tool handles; propellers; fanblades; boat hulls; and sport equipment including baseball bats, hockeysticks, polo and croquet mallets, toboggans, skis and the like. It hasespecial application in the protection of, and extension of the usefullife of, bowling pins which are subject to severe battering in play. Theinvention accordingly will be discussed in conjunction with coatingwooden bowling pin cores although it will be apparent that the system ofthe invention may be applied in coating wood surfaces generally.

The manufacture of bowling pins by first preforming a bowling pin coreor body from a suitable hardwood and then applying thereto any ofvarious coating materials comprising a plastic cover is known. While ithas been possible in the past to produce bowling pins which areattractive in appearance and have substantial resistance to destructionfrom the rigors of play for a period of time, the procedure used inproducing these pins has been expensive and time consuming. Also thecoating materials have been costly and difiicult to apply. Moreover, theuseful life of pins produced by the prior art methods has always beenfar shorter than is desirable.

We have discovered that excellent protection may be imparted to woodsurfaces by applying thereto a film of certain hydrophilic compoundssuch as amylose. When applied to wood bowling pin cores, prior toapplication of the relatively thick plastic protective coating, suchfilms are found to extend the useful life thereof very markedly. We havefound that such films provide very tenacious prime coating which iscompatible with the wood constitution, and with the subsequently appliedprotective organic plastic layer. The film-forming substancescontemplated are all derivable from natural occurring materials andinclude polysaccharides such as amylose and derivatives thereof; highamylose starches and chemically modified starches; hydrophilicfilm-forming natural gums, and protein.

It is an object of the invention to provide a novel tenaciously adheringcoating system for wooden surfaces which imparts improved impact anddeterioration resistance to surfaces of this type. It is a furtherobject of the invention to provide an expensive coating for wood whichis applied from an aqueous medium. It is a more specific object of theinvention to provide a novel method of pro- 'ice tectively coatingwooden bowling pin bodies. It is a further object of the invention toprovide a novel primerimpregnant for wooden surfaces. Additional objectsand advantages of the invention will become apparent from the moredetailed description of the invention provided hereinbelow.

By conducting life tests with bowling pins constructed in many differentways, we have found that the relatively short useful life of pins madefrom hardwood bodies by the methods of the prior art is due to a largeextent to the failure of the bond between the respective protectivecoatings applied to the hardwood body. It is due also, verysubstantially, to failure of the wood itself, as by crushing of the woodfiber. In the ball-impact area of the pin, the pin body is repeatedlysubjected during play to very severe concussive forces. The crushing ofthe fibrous structure of the wood is most severe at, and adjacent to,the surface of the ball-irnpact area. The rate of deterioration of thewood core depends on the various factors in addition to impact, such asmoisture loss. The consequences of wood failure are rupture of the coreand loss of the surface coating or coatings carried thereby. Once thefibrous orientation of the wood structure begins to fail, the pin israpidly rendered unattractive and unusable. Damage may be of variouskinds such as: cracks in the coating or coatings; separation, splittingand loss of coating material; change in diameter of the pin in theball-impact area due to dehydration and compression; deterioration ofpin rebound characteristics; and the like.

We have discovered that the life of Wood substrates is verysubstantially upgraded by applying, from a dilute aqueous dispersion, adeposit which fills the interstices of the wood, penetratessignificantly into the pore of the wood and intimately and tenaciouslyadheres thereto. The treatment further provides a bulking or stabilizingeffect for the composition of the wood. When dried, the film depositcomprises a layer of resin which has penetrated into the wood body to asubstantial depth, has intimately bonded the fibrous structure of thewood, and provides a continuous layer on the surface of the wooden body.

In order that the manner in which these and other objects are attainedin accordance with the invention can be understood in detail, referenceis made to the accompanying drawing wherein:

FIG. 1 is a view, partly in section of a bowling pin produced inaccordance with the invention.

FIG. 2 is a fragmentary sectional view, enlarged in scale, illustratingthe various layers of a four-layer coating system for a wooden surface.

FIG. 3 is another fragmentary view illustrating a twolayer coatingsystem.

The invention can be best understood by describing the coating proceduregenerally with reference to the drawing.

FIG. 1 illustrates one form of pin which can be made in accordance withthe invention and which comprises a pin body 10 of maple or otherhardwood, the body being coated with a synthetic resinous material, asindicated at 11, to reinforce and protect the wood. The layers of theplastic coating, as more clearly shown in FIG. 2, comprise a first layerof the water-dispersible material 13 of the invention deposited upon thewooden substrate 12. Subsequent coatings comprise an optional sealercoat 14, a relatively thick gel lacquer coat 15 and a topcoat 16. In theembodiment of FIG. 3, the pin body has a prime or first layer asdescribed in FIG. 2 but contains a single subsequent outer layer 17, inlieu of the multiple layer system 14, 15 and 16 illustrated in FIG. 2.

The penetration of the prime coating anchors the film to the texture ofthe wood and substantially aids in pre- Patented Nov. 30, 1965 ventingseparation of the resin coating from the wood base, as generally occurswith organic solvent-soluble films which present a sharply defined ordistinct separation between coatings. The nature of the prime coats issuch that it provides a cushioning effect to resist the severe blows onthe pin by distributing the shock over a larger area of the pin body.

In accordance with the invention, a hydrophilic film comprising amaterial of the group consisting of polysaccharides or protein whenapplied to the wood surface prior to coating with organic coatings,produces very definite advantages. The hydrophilic film on the foodsubstrate behaves as a buffering zone between the wood, which has atendency to give up water, and the organic plastic protective shell,which comprises the protective cover and is incompatible with water. Inthe absence of this buffering film or barrier, of the character providedby the present invention, water evaporated from the wood contacts theorganic layer and results in heaving, or separation of the coating fromthe wood core in a relatively early stage in the life of theplastic-coated wood article. When the film of hydrophilic material ispresent as a barrier between the wood surface and the relativelyhydrophobic organic coating, water evaporated from the wood is absorbedby the film and in effect smooths out the tendency of the wood core tochange in dimension from loss of water. The chemical composition of thehydrophilic film is such that it is completely compatible with thecellulose composition of the wood; it penetrates the surface of thewood; and it provides reinforcement.

Upon the surface of the pin containing the prime layer, may optionallybe applied a conventional coating which comprises a relatively thin,substantially vapor-impervious sealing film or coat 14. For thispurpose, nitrocellulose or other composition which is firmly adherent tothe prime layer 13 on the wood pin body 12 may be used.

Continuously overlying the sealing coat 14 and uniformly bonded theretois a relatively thicker protective gel coat 15. This protective coat mayin turn be coated by a relatively thin dirt-repellent topcoat 16.

Penetration of the primer-impregnant hydrophilic film into the woodinterstices may vary to depths of from about 1 to about 250 milsdepending on the viscosity and means of application. The continuouslayer or deposit over the wood surface may vary from about 0.1 mil toabout 50 mils and depends also on variable factors such as thecomposition and concentration of the aqueous dispersion. The sealingcoat 14, when employed, is generally of the order of 2-12 mils althougha thicker film may be employed. The subsequent protective coat 15 is ofmore substantial depth having a thickness of the order of 25-75 milsalthough thicknesses up to 250 mils may be employed. The finish topcoat16 is of conventional thickness, generally varying from about 0.5 mil to12 mils but may be as thick as 40 mils or more where practical anddesirable. It will be understood that the invention in essence residesin the use of a hydrophilic primerimpregnant surface layer on wood andthe bond thereof with the fibrous composition of the wood. Also, ofimportance is the bond of the primer-impregnant with subsequent organicprotective layers. The invention is not limited by the application orcomposition of the protective or finish coatings which overlie theprimerimpregnant layer and which are described herein for the purpose ofproviding a fuller understanding of the invention and its environment.Accordingly, as shown in FIG. 3, a single coating may be applied overthe primer-impregnant layer of the invention in lieu of the three-coatsystem 14, 15 and 16 of FIG. 2. For this purpose, a cured polyurethaneresin such as that available commercially as Adiprene may be used, forexample.

Having thus generally described the nature and mannor of applyingcoatings to wood surfaces, a more detailed procedure is provided hereinbelow in which bowling pins are manufactured in accordance with theinvention.

PRIME COAT COMPOSITION The primer-impregnant contemplated for treatmentof wood surface according to the invention comprises hydrophilicfilm-forming polysaccharide compounds, including modifiedpolysaccharides and protein.

The water-soluble hydrophilic film-forming polymers contemplated withinthe invention are those which effectively treat the exterior nature ofthe wood by reinforcing and physically sealing the porous structure. Theadvantages of the hydrophilic film on the wood is due to theintermolecular linkages of the hydrophilic composition with thecellulose of the wood through such forces as hydrogen bonding and Vander Waals forces. These forces or bonds are distinguishable from thetrue chemical or co-valent linkages. In essence, the nature of thesepolymers is such that they are of a type that are nonchemically reactivewith hydroxyl groups. Materials contemplated as useful in forminghydrophilic films in accordance with the invention are carbohydrates andmore specifically polysaccharides and derivatives of polysaccharidessuch as amylose, derivatives of amylose such as the esters of amylose,the ethers of amylose and the oxidized amyloses; hydrophilicwater-dispersible gums such guar, locust bean gum, tragacanth, theoxyalkyl celluloses, e.g., hydroxyethyl cellulose, carboxymethylcellulose; and proteins, including animal and seed proteins such ascasein, blood albumin, soy, cottonseed, rape seed and tung. Each ofthese hydrophilic materials are soluble or dispersible in water orcapable of solubilization in aqueous media which includes slightlyalkaline aqueous medium. Significantly these film-forming materials arecharacterized by being substantially insoluble in all common organicsolvents and consequently do not interfere in standard coatingprocedures utilizing organic solvent soluble resinous systems which areapplied over the hydrophilic layer of the invention.

In addition to amylose, which is preferred primerimpregnant, waterdispersible derivatives of amylose such as hydroxyethyl amylose, methylamylose, carboxymethyl amylose, hydroxypropyl amylose, ethylhydroxyethyl amylose, ethyl amylose, amylose acetate, carbamylethylamylose and the like may be used. Derivatives of amylose or amylosecontaining film-forming materials having an excess of 50% amylosecontent as determined by conventional idiometric analysis are preferred.As such for example, fractions of starch, derived from various sourcessuch as corn, wheat, potato, tapioca, and high amylose corn starch,sodium salts of ungelatinized low substituted starch acid esters and thelike may be employed.

In general, concentrations in the aqueous medium of from about 1% to 40%of the film-forming material and preferably from about 2% to 30% ofsolids may be employed. With high viscosity materials such as guar,locust bean gum, or agar-agar below about 10% and preferably below about5% may be adequate. While with proteins and some low viscosityderivatives of amylose and cellulose up to 30% or greater concentration(parts of film-forming material per parts of water) may be used withhigh amylose starch from about 1% to about 18% and preferably from about3% to about 10% is employed.

Wood primed by applying films of the foregoing from aqueous solutionshave very definite advantages in economy, coating periods and facilityin processing times and procedure. The pins are fully coated after 15minutes residence time. The variation in core weight is less than withknown organic solvent soluble resin prime coats or with Water basedemulsions of the vinyl acetate or copolymer type. Within about threehours after the pins are coated, they are normally sufliciently preparedby air drying to be subsequently coated with organic solvent filmforming compositions. By applying heat to the coated substrates, dryingperiods as low as 15 minutes may be adequate. The primer-impregnantlayer functions as a barrier between the water and the organic-solubleresin thereby moderating changes in the moisture content of the wood. Italso prevents penetration into the wood, of water incompatible organicresin and solvent, during the later coating steps. The increaseddurability of pins coated with the hydrophilic impregnant layer of theinvention over commercial wood pins, wherein organic impregnants areemployed, is believed due to the formation of secondary bonding forcesbetween the Wood and the hydrophilic impregnant. The impregnants such asamylose, for example, generally have chemical compositions similar tocellulose of the wood and have a strong afiinity therefor. The effect ofthe impregnant on the wood can be further strengthened by derivatizingthe film on the wood substrate as by dipping the film-coated woodarticle into a suitable reaction mixture. With amylose films, forexample, a reaction mixture containing acetic anhydride and catalyticamounts of sulfuric acid may be used. Cross-linking of the film, such asby treatment with formaldehyde or glyoxal, may also be effected in alike manner.

The film-forming composition used as impregnant may contain variousadditives of the type conventionally utilized in the art to effectvarious results such as gel inhibiting or retarding agents, e.g.,formaldehyde, NaOI-I; plasticizers, e.g., glycerine, sorbital;flexibilizing agents, and the like. The term aqueous dispersible asemployed herein is contemplated as inclusive of and generally usedinterchangeably, where applicable, with soluble. Further, as usedherein, aqueous dispersible means soluble in water to the extent of atleast 0.2% by weight and includes colloidal aqueous media.

The following examples, in which the parts recited are parts by weight,are provided in order that the invention may be better understood. Theexamples are illustrative only and should not be interpreted asindicative of limitations on compositions or conditions stated.

In protectively coating wooden bowling pin cores, the following generalprocedure may be employed. The details relating to applying protectiveand finish coatings over the prime coat are presented only as an aid inproviding a more complete description and not as a limitation of theinvention presented.

Wood cores of proper weight and dimensions are first convenientlysupported to facilitate handling such as by inserting dowels in the headof the pins. The doweled cores are then placed in racks and secured inplace. The arrangement is such that preferably throughout the coatingprocess the cores remain on these racks. These racks are preferably fed,in a continuous manner, through the primer-soak units in which the coresare impregnated with the primer solution. The impregnating period variesas desired or as necessitated by conditions or compositions used. Theprimer-coated pins are then dried. Room temperature drying with forcedair is relatively rapid and is preferred although drying times may beaccelerated at elevated temperatures.

In a multiple coat system of sealer coat, gel coat and topcoat over theprimer, the sealer material is next applied to the primed cores. Anysuitable means of applying the sealer may be used. In so treating thepins, racks of primed, dried cores are fed to the sealer operation wherethe sealer solution is applied over the primed core surfaces. If morethan one coat of sealer is applied, each sealer coat is preferably givenan interim drying period. Optionally, the sealer coat may be omitted andpreferably it is replaced with a second application of the hydrophilicprimer-impregnant film-forming compositions as taught by the invention.The second application may be either of the same or differentcomposition. For example, an amylose prime coat may be topped with aguar gum before the organic solvent protective coating is applied.

After proper drying, the sealed cores are readied for application of thegel protective lacquer. For this purpose, ethyl cellulose is preferred.A dipping operation is preferably employed. At predetermined timedintervals, the prepared articles are dipped into protectivecompositions, generally comprising a gel-lacquer, at a constanttemperature and Viscosity, and a uniform coating of desired thickness isachieved. One or more dip applications of the pins in the lacquer may beemployed. At least some drying is preferably conducted after eachprotective coating dip or application to aid in preventing sagging andminimize total drying times.

After the relatively thick gel coating has dried sufficiently, a thinclear lacquer coating is preferably, although optionally, applied bysuitable means. Subsequent drying is preferably conducted at moderatetemperatures, e.g. from about 70l50 F. for a minimum period of from 15minutes to 5 or 6 hours or more.

At this point, the coating operation is complete and variousconventional finishing operations may be performed on the coated pins:e.g. dowel removal, bottom facing, striping, insignia or decalapplication, weighing, grading and the like. An aging period to effectthorough chemical cure of the plurality of layers comprising the plasticshell may be advisable depending on the treatment used before the pinsare applied to lane use.

In the examples which follow, unless otherwise provided, theprimer-impregnant described in the examples was followed by coating atroom temperature, first with a sealer coat (about 3-12 mils) ofnitrocellulose 8% solids; next with a titanium dioxide pigmented gellacquer coating of ethyl cellulose (about 25-60 mils) obtained by threedips in the gel lacquer and then a finish coat (about 2-l2 mils) of10.5% solids nitrocellulose.

Example 1 Twenty-four preformed hard maple bowling pin cores are soakedfor 15 minutes in a 13.4% solution of amylose. The amylose immersingsolution is prepared as follows: 18 parts by weight of amylosecommercially obtained as Superlose from Stein, Hall & Co., Inc. isslurried in parts of Water and heated at 160 C. in an autoclave untilthe amylose is solubilized. The solution is stabilized with formaldehyde(7% based on amylose solution) and diluted to the above (13.4%)concentration. The pins are removed and dried overnight at roomtemperature. Thereafter the pins are further coated using the proceduredescribed above with 3 sealer coats of nitrocellulose (total about 5mils thick) 3 gel coats of ethyl cellulose (about 70 mils) and onetopcoat of nitrocellulose lacquer about (2 mils thick). The bowling pinsprepared above are subjected to actual play and compared with commercialplastic coated pins. After 2000 lines of play none of the amylose primedpins show any evidence of cracks or failure in the coating system. Thecommercial control pins have definite signs of deterioration; after 1500lines substantial cracking and chipping of these control pins hadoccurred, particularly at the ball-line.

Example 2 The procedure of Example 1 is repeated with the exception thata 14% aqueous solution of hydroxyethyl amylose is employed instead ofthe amylose of Example l. The pin cores are retained in this solutionfor a residence time of 12 minutes. The hydroxyethyl amylose solution isprepared by dispersing 14 parts of hydroxyethyl amylose available asSuperlose HAA-l 1-HV, from Stein, Hall Co., Inc. by stirring whileheating to C. for about 10 minutes into 86 parts of water until thesolution is clear. The pins are air dried at room temperaure overnightand finished as in Example 1 with 3 sealer coats, 3 gel coats and 1topcoat.

Example 3 The procedure of Example 1 is substantially repeated with theexception that a 2% agar-agar gel dispersion prepared by stirring 2parts of agar in 98 parts of water on a bath of boiling Water. The agarsolution is maintained above about 40 C. while the pins are immersed inorder to prevent gelation of the solution. The pins are thereafterfinished with the sealer coats, gel coats and topcoat as in Example 1.These pins also have characteristics superior to organic solvent primercompositions.

Example 4 The procedure of Example 1 is substantially repeated with theexception that a 15% solution of low viscosity sodium alginate isemployed instead of the amylose solution of Example 1. After drying atroom temperature overnight, the pins are finished by applying thesubsequent coats as in Example 1.

Example 5 The procedure of Example 1 is substantially repeated employingin place of the amylose solution a solution of parts of carboxymethylamylose in 85 parts of hot water 85 C. with constant agitation. Theresidence time of the pins in the dispersion is minutes. The pins arethereafter coated as in Example 1 with the sealer coats, gel coats andtopcoat.

Example 6 Forty hard maple bowling pin cores are primed with amylose inthe manner described in Example 1 and dried. Thereafter in lieu of thesealer coat, gel coat, and topcoat, a single coating comprisingpolyurethane is applied by dipping the pins in the liquid composition.The polyurethane liquid composition is prepared by mixing 100 parts byweight of urethane prepolymer obtainable as Adiprene L-100 from E. I. duPont de Nemours & Co. Inc., and mixed with 6 parts by Weight of 4,4methylene bis(2 chloroaniline) as catalyst. The amylose prime pins arethen immersed 3 times in this liquid organic composition until a coatinghaving a thickness of about 50 mils is deposited. Preferably after eachdip, the pins are dried for about 30 minutes at a temperature of 50 C.and thereafter cure is completed by 3 hours bake at 212 F.

Two randomly selected bowling pins from each batch prepared according toExamples 1 to 6 were subjected to repeated impacts on a laboratoryimpact testing apparatus, the tests being continued until the pins hadbeen subjected to 6000 impacts directed at the ball-line on the impacttester, representing approximately 2500 lines of actual bowling alleyservice. Each of the test pins were then substantially free of hair-linecracks in the composite coating, had excellent surface appearance,exhibited little loss of coating material and little change in ball-linediameter. Each of six pairs of commercial pins used as control in thesame test Were visibly more deteriorated. Each of the control pins hadvery substantial cracks and chips in the coating.

Example 7 Ten parts of sodium casein is dissolved in 90 parts of waterat 35 C. while stirring. The water contains 0.5% of thymol aspreservative. Twenty-four wood pins are dipped in the solution and heldfor a residence time of 30 minutes. The pins are then primed and furthercoated in the manner described in Example 1.

Example 8 Thirteen parts of amylose containing 0.1 part of sodium metabisulfite is mixed into hot water (90 C.) and then heated to 160 C. inan autoclave to insure complete solution. The temperature of amylosesolution is maintained above 70 C. to retard gelation. Twentyfour pinsare primed in the manner described in Example 1. At this point the pinsare air dried and then passed into a bath containing acetic anhydrideand catalytic amounts of H 80 Residence time is 15 minutes. The

pins are dried by hot air at 60 C. and further coated as in Example 1.

Example 9 A 3% solution of guar (available as Jaguar Industrial Gum fromStein, Hall & Co., Inc) solution containing 0.5% formaldehyde as apreservative is prepared and then poured over twenty-four bowling pinswhich have been preheated in a vacuum system. The pins are dried in .ahot air oven at a temperature of 50 C. for 90 minutes. The pins are thenfurther coated with layers of nitrocellulose and ethyl cellulose in amanner similar to that described in Example 1.

Example 10 750 parts of water containing 0.5 preservative thymol isheated to 55 C. under constant agitation. Then 200 parts of lowviscosity soy protein (obtainable as ADPRO 410 from Archer DanielsMidland Co.) is added to the solution. The temperature is adjusted to 55C. and the blend is stirred for ten minutes after adding the protein.Then 5.5 parts of NaOH is dissolved in 45 parts of water and added tothe protein slurry The stirring is continued for 20 minutes at 55 C.until all protein is dispersed. Twenty-four pins are dipped in asolution for 5 minutes, dried, sealed and coated in the manner describedin Example 1.

Example 11 The procedure of Example 10 is employed except that the wetpins lifted from the soy solution are then dipped into a second bathcontaining 2% formaldehyde solution for two minutes prior to furthercoating. The pins are then dried in a hot air oven at 35 C. for 4 hoursand further coated as in Example 1.

In this example, treatment of the deposited film with the formaldehydesolution results in substantial crosslinking of the film.

Example 12 The procedure followed in Example 10 is repeated with theexception that a 20% protein solution prepared from soy protein,available ADPRO 112 from Archer Daniels Midland Co. is used, containing3% sodium hydroxide based on protein content dissolved in the primerdispersion. Subsequent coatings are applied as in Example 1.

Example 13 Five parts of carboxymethylcellulose, medium viscosity gradeHercules Powder Co., is introduced into and mixed under constantagitation in 95 parts of water at C. and mixed until very smooth.Twenty-four maple pin cores are dipped into and retained in thissolution for 30 minutes, air dried for 1.5 hours and thereafter furthercoated in the manner of Example 1.

Example 14 Ten parts of hydroxyethylcellulose is sifted slowly into 90parts of water while rapidly stirring and stirred vigorously untilcompletely dissolved. Twenty-four wood pin cores are then prime coatedand further coated in the manner described in Example 1.

Example 15 Fifteen parts of carboxymethylcellulose (low viscosity grade,from Hercules Powder Co.) is stirred with agitation into parts of water.After complete solution of the gum, twenty-four maple bowling pins aresoaked for 15 minutes, dried at room temperature for 3 hours and coatedin a manner similar to Example 1.

Example 16 Two parts of ethyl hydroxy ethyl cellulose is dispersed into98 parts of cold water (25-30" C.) under constant agitation untilcompletely dissolved. The resulting gum solution is deaerated bycentrifugation. Twenty-four maple bowling pins are then dipped into thissolution for a residence time of minutes; dried and further coated inthe manner described in Example 1.

Example 17 Two parts of locust bean gum is stirred into 98 parts ofwater at 25 C. and allowed to hydrate for 2 hours. The mixture is thenfurther stirred for 2 minutes. Twenty-four maple pins are dipped in thissolution for a residence time of 30 minutes and coated in the mannerdescribed in Example 1.

Example 18 Example 19 A mixture is prepared comprising 3 parts ofhydroxyethyl amylose prepared according to the procedure of Example 2and one part of the hydroxyethylcellulose dispersion as prepared inExample 14. Twenty-four pins were soaked for minutes in this combinedblend. After air drying, the pins were further coated with polyurethanein the manner described in Example 6.

SEALING COMPOSITION In general, any conventional lacquer which upondrying produces an adhering substantially impermeable film can beemployed to provide the optional sealing coating 5, see FIG. 2, over theprimer-impregnant hydrophilic layer of the invention. The sealercomposition must be of such nature that it provides a uniform andcontinuous relatively thin film over the entire primed surface of thebowling pin body, the film being capable not only of adhering securelyto the primer but also should aid in assuring that gases which areentrapped in the wood of the bowling pin bodywill not pass into contactwith the protective organic layer either during application or curing ofthe protective coating 15 or during the useful life of the wood article.Although the primer of the invention may be employed in conjunction withan auxiliary sealer, it is of itself in appropriate thickness anadvantageous sealant or barrier.

Various'cellulose esters may be suitably utilized as auxiliary vaporbarriers. The following formulation is illustrative for cellulose esterlacquer sealing coat compositions which may be adapted for use inaccordance with the invention.

Ingredient: Parts by weight Nitrocellulose 7.0 Ethyl acetate 45. Toluene30.0 Ethanol 15.0 Dibutyl phthalate 2.2 Alkyd plasticizer 0.2

PROTECTIVE COAT COMPOSITION The protective coat 6 is of substantialthickness and generally comprises a plurality of layers of any one ofvarious compositions known for this purpose. Preferably a compositionproviding a relatively thick coating with each application is used.Various formulations are available commercially for this purpose.Application of these compositions to the substrates may be effected byany convenient procedure such as by hot dip or flow coat techniques. Inhot dipping, coatings varying from about 3 mils to about 30 mils foreach dip are obtainable. Examples of suitable protective coatingsinclude various gel lacquers e.g. ethyl cellulose, cellulose acetatebutyrate, polyurethane compositions, generally containing suitablepigmentation, such as titanium dioxide, and plasticizer, such asdioctylphthalate, dibutylphthalate, etc. Ethyl cellulose gel lacquersare particularly advantageous. A protective coat comprising multipleapplications of nitrocellulose lacquer solutions may also be employedfor this purpose. The following is typical of gel lacquers that areuseful and can be applied over the substrate prepared in accordance withthe invention.

Ingredient: Parts by weight Ethyl cellulose 316.0 Xylene 610.0 Ethyleneglycol monoethyl ether 278.0 Petroleum naphtha 222.0 Titanium dioxidepigment 7.0 Alkyd plasticizer 7.0

1 cps., medium ethoxy.

2 (;See note 2 for sealing composition.)

This composition is applied to the impregnated bowling pin body bydipping the body in the lacquer composition while maintaining thelacquer composition at approximately 200 F., the bowling pin body thenbeing withdrawn at a controlled rate over a 5 minute cycle, althoughthis cycle is not critical. The dipping operation is repeated threetimes (although more or less dips may be suitable). Preferably themultiple layers should provide a coating of at least 25 mil thickness.The pins are dried for 2 hours at F. after each of the first two dips,and for 1 /2 hours at 180 F. after the third dip.

The particular solvent composition employed in this example is soprepared as to provide for slight dissolution or swelling of thenitrocellulose of the sealing film 14, so that the protective coat 15 ismore securely adhered to the sealing film.

TOP COAT COMPOSITIONS Any conventional lacquer suitable for providing anattractive, glossy, dirt-repellent topcoat can be employed for coat 16.As such for example, compositions comprising polyurethane,polycarbonates, acrylics, vinyls, shellac, polystyrene and the like maybe employed and modified where desired with suitable solvents,plasticizers etc. Advantageously, a composition containing aconventional nitrocellulose base is used. Compositions such as thefollowing provide excellent top coats.

1 1A, see. viscosity.

9 5-6 see. viscosity.

Such compositions are applied by flow coating followed by drying atsuitable temperatures and for appropriate times, e.g. about 30 minutesat approximately 100 F. Dip or spray coating techniques and/or airdrying of the coated pin may also be employed.

In lieu of the three subsequent coatings applied to the primed wood, asingle coating of resinous composition may be employed as described inconnection with FIG. 3. For this purpose, for example, a polyurethane,resin available commercially as Adiprene from E. I. du Pont de Nemours &Co., Inc., as described in Example 6 may be used.

A plurality of layers of such compositions are generally employed withpreferably at least partial drying between each layer or dip. In coatingbowling pin cores, satisfactory results are obtainable, also by placingthe undersized core treated with the primer-impregnant of the inventionin a mold and casting a plastic shell over the pin body.

It will be apparent to those skilled in the art that the present methodcan be modified in various ways without departing from the scope of theinvention. For example, where it is desirable to accomplish extensivepenetration of the prime coat composition or to accelerate theapplication thereof, the wood bowling pin bodies can be heated prior tobeing immersed in the impregnating liquid, the resulting cooling of thepin bodies producing a vacuum elfect by reason of condensation of vaporsin the pores of the wood, so that impregnation is enhanced. Other typesof vacuum impregnating procedures can be employed with similar efiect.Conversely, impregnation can be accomplished under elevated pressures,so that deeper short-time penetration of the prime coat composition soobtained relative to results obtained from the case of simple soaking.

Various changes will be apparent to those skilled in the art in thepractice of the invention. It is therefore understood that theenumeration of certain details, for the purpose of illustrating theinvention, should not be considered as a limitation on the inventiveconcept provided herein nor restrictions on the scope of the inventionexcept as provided in the appended claims.

We claim:

1. A wood article wherein the wood is impregnated with an amylosesolution and coated with a resinous composition selected from the groupconsisting of ethyl cellulose and polyurethane.

2. A wood article wherein the wood is impregnated with an amylosesolution and coated with a first coat of nitrocellulose and a secondcoat of ethyl cellulose.

3. Wood impregnated with a primer consisting essentially of apolysaccharide material selected from the group consisting of amylose,an ester of amylose, an ether of amylose, an oxidized amylose and anoxyalkyl cellulose.

4. Wood impregnated with a primer consisting essentially of amylose.

5. Wood impregnated with a primer sentially of an ester of amylose.

6. Wood impregnated with a primer consisting essentially of an ether ofamylose.

7. Wood impregnated with a primer sentially of an oxidized amylose.

8. Wood impregnated with a primer sentially of an oxyalkyl cellulose.

9. A synthetic plastic coated wood bowling pin whose wood core isimpregnated with a primer consisting essentially of a polysaccharidematerial selected from the group consisting of amylose, an ester ofamylose, an ether of amylose, an oxidized amylose and an oxyalkylcellulose.

10. A synthetic plastic coated wood bowling pin whose wood core isimpregnated with a primer consisting essentially of amylose.

11. A synthetic plastic coated wood bowling pin whose wood core isimpregnated with a primer consisting essentially of an ester of amylose.

12. A synthetic plastic coated wood bowling pin whose wood core isimpregnated with a primer consisting essentially of an ether of amylose.

13. A synthetic plastic coated wood bowling pin whose wood core isimpregnated with a primer consisting essentially of an oxidized amylose.

14. A synthetic plastic coated wood bowling pin whose wood core isimpregnated with a primer consisting essentially of an oxyalkylcellulose.

References Cited by the Examiner consisting esconsisting esconsistinges- UNITED STATES PATENTS 1,297,491 3/1919 Powell 117147 1,732,41910/1929 Rice 117-148 1,785,571 12/1930 Allen 117-148 1,918,691 7/1933Fawkes et al 117-147 X 2,128,962 9/1938 Patterson 117-147 2,716,6128/1955 Marks et al 117-84 2,804,399 8/1957 Kelly et al. 117-85 2,804,4008/1957 Kelly et at. 117-148 X 2,901,467 8/1959 Croco 117-148 2,988,4556/1961 Rosenberg 106-197 X 3,018,106 1/1962 Satchell 27382 3,046,2727/1962 Stratling 106-294 3,054,755 9/ 1962 Windemuth et al. 117-48 X3,080,257 3/1963 Berry 117-148 X OTHER REFERENCES Senti: Research toUtilize Amylose, Chemurgic Digest, May, 1958.

WILLIAM D. MARTIN, Primary Examiner.

RICHARD D. NEVIUS, Examiner.

1. A WOOD ARTICLE WHEREIN THE WOOD IS IMPREGNATED WITH AN AMYLOSESOLUTION AND COATED WITH A RESINOUS COMPOSITION SELECTED FROM THE GROUPCONSISTING OF ETHYL CELLULOSE AND POLYURETHANE.